It took me just one, 40-mile ride—climbing Malibu's Yerba Buena Road and dropping down into Decker Canyon—to become convinced that Cervélo's new Rca is the ultimate high performance bike. I had high expectations, and this bike exceeded them all: Nothing I’d ridden previously combines low weight, stiffness, handling, aerodynamics, and comfort in the sublime way that this bike does. Of course, at $10,000, this oligarch-only frame—of which only 325 will be made—should be among the best I’ve ever tested.

On the road, the bike felt solid, significant, and confidence inspiring in my hands and under my feet. The geometry is proven—shared with other R-series bikes—which helps make it the best-descending Cervélo I’ve ever ridden, and one of the best-descending bikes I’ve tested from any brand. Marrying those angles with a frame that doesn’t dilute little motions and small changes in power makes it reactive and quick. It’s also stable, remaining composed in rough corners, and providing me with superb feedback.

But the wonder of this bike is not only in how it rides—after all, your chances of riding, or even spotting an Rca outside WorldTour races, are infinitesimal. The real magic lies in the experiments with high-tech materials, and the lessons that Cervélo learned in building this wonder bike—technological gains expressed in a language native only to lab technicians wearing white coats. Hopefully, this bike’s tech will be passed on to the company’s production bikes in the coming seasons.

High-Tech Machine
In hatching a descendant of the 689-gram R5ca, Cervélo needed to raise the bar. That bike was exceptionally light and stiff. Cervélo says that three years after its debut it is still the lightest frame in the world, with the highest stiffness-to-weight ratio. But it was not designed with any regard for aerodynamics. However, Cervélo’s wind tunnel testing showed that the R5ca performed better than many traditional road bikes.

With that insight came another: Adding just a little attention to aero shaping, a new bike could capture aero gains and maintain the R5ca’s superlative characteristics. Of course, combing those three traits—aerodynamic efficiency, stiffness, and low weight—presented engineers with a challenge. Typically, road bike designers need to choose two of those three traits, and compromise on the third.

The Rca’s magic was readily apparent on our first ride. (Courtesy)

Cervélo developed the Rca using a suite of software tools, two of which are well known in the bike industry: Finite element analysis (FEA) helped the company evaluate structural performance and computational fluid dynamics (CFD) evaluated the aero performance. A third program, called Laminate Tools, is less common. Cervélo used it to understand how each individual piece of carbon in the frame functions. That's a large task: A 54cm Rca is comprised of 459 plies of composite, and uses seven different fiber materials, in 14 different orientations.

Computer modeling is helpful, but once the designs were set, Cervélo turned to another resource that’s unusual in the cycling industry: Their own carbon manufacturing facility in Garden Grove, California, where every Project California bike is built. Because they own the facility (rather than contracting out manufacturing, a common practice), Cervélo can perform research and development quickly, testing various iterations and developing manufacturing technologies in-house that improve their frames. Plus, its location—amid facilities used by the United States’ defense and aerospace industries—gives them quick access to expertise and the latest materials.

More Aerodynamic
Using these tools, Cervélo designed 93 computer models of different frames before arriving at what became the Rca. The new bike reduced the frame’s weight by 30 grams and incurs 74 grams less drag than the R5ca—and 102 grams less drag than a Cannondale SuperSix Evo or Specialized Tarmac SL4—which saves a rider 7.4 watts at 40 km/h. For riders who only care about aerodynamics, Cervélo says its S5 is still the top of the heap—it generated 140g less drag, but weighs 300g more; an 54cm Rca frame with paint and hardware weighs 667 grams.

The most obvious difference between the Rca and the R5ca it’s replacing—and the source of its aerodynamic gains—are the tube shapes. The tubes are “squoval” (squared oval), like on the R5ca, but have been revised with a "nose" on the leading edge, and redesigned corners on the trailing edge. The shaping (called Squoval3) is applied only where it serves an aerodynamic purpose: The down tube is quite square at the top because, Cervélo says, "[it] is drafting in the wake of the front wheel, so aero shapes are less important and structural considerations can drive the shape." But, further down, where the tube is exposed to more direct airflow, the tube gets the aerodynamic-enhancing nose. The result is a bike with some tubes that look similar to those found on the Scott Foil and the new Trek Madone, but Cervélo doesn’t share “Kamm Tail” or, “truncated airfoil,” nomenclature used by other brands.

The down tube transitions from a square shape at the head tube to the Squoval3 design toward the bottom bracket. (Courtesy)

The hourglass-shaped head tube, minimalist seatstays, and seat tube have also been optimized to slice through the air. The top tube and chainstays don't have a nose because they have, "virtually no effect on aerodynamics," the company says. Instead, they are optimized stiffness and comfort, and to reduce weight.

New Materials
The Rca is the first bicycle to incorporate two new composite material technologies. One is a nano-resin from 3M called PowerLux, just launched in February. The typical nano-resin is a nano-rubber, but PowerLux is a nano-silica resin. Nano-rubbers, says Cervélo, increase toughness at the expense of interlaminar shear strength (strength between layers) and compression strength. The nano-silica PowerLux improves both toughness and interlaminar sheer and compression strength. What does the jargon mean to you? Cervélo can use less material to further reduce weight, without weakening the frame. Of course, PowerLux is expensive—seven times more costly than the other composites used in the Rca—so it is only used in three areas, the down, seat, and top tubes.

The other new material in the Rca is called Powermetal Nanovate, a nickel-plated carbon. Compared to other carbon materials, this one’s grains are 1000 times smaller, but still have a yield strength (point at which a material permantently deforms) that’s seven times that of typical nickel grains. Cervélo applies it to the fork steerer where, they say, it improves toughness without adding weight. A tougher steerer should improve its resistance to damage from over-torqued stem clamps, crashes, and handling mishaps that can lead to failure.

Bulkheads
One of the features pioneered in the R5ca and carried over to the Rca are internal reinforcement walls that Cervélo calls bulkheads. The company says that large diameter, thin walled carbon tubes can buckle, slightly, when subjected to high loads. One method to counter this effect is to increase the wall thickness of the tube, but that adds weight. Instead, Cervélo found that adding bulkheads to brace the walls results in similar stiffness gains with less additional weight than thickening the tube walls. The Rca has bulkheads in the down tube at the head tube, seat tube at the top tube, and above the bottom bracket shell.

The Little Details
In addition to several marquee technologies, Cervélo enhanced the Rca with a number of other small details.

The bike has a fully internal, "future proof" cable routing system with an interchangeable click-in stops and blanks that accommodate mechanical, electronic, or even hydraulic systems. The derailleur cables enter the down tube behind the head tube because Cervélo feels it's better to cut holes in the top of the tube where there’s less stress, rather than the sides. The drive-side chainstay is at a slightly different angle than the non-drive stay, so a mechanical shift cable can run from the bottom bracket out though the dropout without a bend, for better shifting.

Cervélo found 5 grams of weight savings in the dropouts, into which the stays are bonded, reversing the method used on most carbon bikes. This results in less redundant material—and the weight savings.

The Rca also uses Cervélo's BBright bottom bracket standard, but the company tweaked it slightly, filling in some unused space on the outside of the chainstays and opening up the inside the stays for more tire clearance—the bike easily accommodates 25mm tires, and even some 28mm models will fit.

In a nod towards the proliferation of power meters, the Rca has an integrated neodymium magnet in the bottom bracket area, which will work with crank-based systems from SRM and SRAM.

What It Means to You
While the highlighted features and technologies Cervélo developed for the Rca are only found in this one, rarified, frame, much of those developments will eventually trickle down to Cervélo's mass production bikes. Already, technologies developed for the R5ca—CNC pattern cutting of composites, molded in-carbon bearing races, the BBright bottom bracket, and the bulkheads—are found in production bikes.

Newer materials and processes are often costly, but slowly over time the prices will come down, and we’ll start to see materials like PowerLux and Powermetal Nanovate in other Cervélo bikes—as well as those from other brands.

Some of this bike’s other details may be adopted more quickly—particularly the Squoval3 tube shapes. That alone would improve the aerodynamics with minimal weight gain. The fat-tire friendly BBright, "future-proof" cable routing, built in magnet, dropouts, and "straight shot" drive side chainstay, seem like upgrades that could easily show up in future versions of Cervélo's R, S and P series frames.